Undefeated in battle, a wooden vessel so stalwart it became known as Old Ironsides, the USS Constitution is perhaps the nation’s most famous warship, an abiding symbol of national pride and naval might.

Yet for two centuries, the hundreds of ordinary sailors who served aboard the great frigate during its most famous victories have been forgotten by history, with little known of their lives or sacrifice. They were celebrated in their day, honored with parades on their triumphant returns to Boston. But as the ship’s legend grew, they faded to obscurity.

Now, as Boston joins the nation in commemorating the bicentennial of the War of 1812, their stories are finally being told.

After a decade of poring over archives here and abroad, researchers at the USS Constitution Museum in Charlestown have pieced together the lives of hundreds of seamen and Marines who served on the Constitution during the war. Among the many characters are James Bennett, a freeborn black man who plugged holes from enemy shot and was later killed in the Battle of Lake Erie, and Asa Curtis of Scituate, the ship’s gunner, who was “weatherbeaten and scarred from many years at sea.”

Often starting with little more than a name, researchers spent long hours combing through pension applications and military documents, personal correspondence, and British prisoner-of-war records, to compile profiles of the sailors and provide a fuller picture of the ship’s history.

“It’s always been the missing piece of the story,” said Anne Grimes Rand, the museum’s president, as she walked through an exhibit that highlights individual sailors and the experience of life at sea.

It was a daunting task, one that scholars warned was nearly impossible given the passage of time. But the museum staff, joined by a host of volunteers, pursued the project with a sense of obligation, determined to give the men their due.

“The Constitution is talked about as if it’s its own agent,” said Sarah Watkins, the museum’s director of collections and learning. “We wanted to tell the story of the men who sailed, who steered, who fought.”

Armed with a solid list of crewmen, researchers began searching through archives for leads, relying heavily on pension records and protection certificates that seamen used as proof of citizenship.

“It was like a passport of the day,” said Lauren McCormack, the museum’s bicentennial programs coordinator. “And in the pension records, you really had to tell your story.”

Those archives often provided a foothold that led researchers to other documents — marriage and death records, wills, and census records.

Slowly, breakthroughs came, and lives came into focus. As researchers learned more, they were drawn into the stories, forging bonds with the figures from long ago.

“They started out as names, and they evolved into individuals,” Watkins said. “For us, it’s not just an intellectual pursuit, it’s an emotional connection.”

The bond was particularly strong with David Debias, a freeborn black from Beacon Hill who was just 8 when he joined the crew, becoming a servant for a master’s mate.

Debias was among the crew chosen to sail on the HMS Levant after it was captured by the Constitution. That vessel was in turn seized by the British on its return to the United States. He was imprisoned in Barbados for a few months before being sent home to his family.

He was discharged in 1815, earning $32 for his seven-month stint.

But Debias was soon back on the seas again, joining the merchant fleet and then reenlisting on the Constitution. In 1838, he left his ship while it was docked in Alabama and was seized in Mississippi as a runaway slave.

Researchers found a letter that a lawyer for Debias wrote the secretary of the Navy, asking for proof of his military service. But they couldn’t find a response and worried the path had gone cold.

“We all wondered, ‘What happened to David?’ ” Watkins said.

Then one day, the National Archives called, saying they had tracked down the Navy’s response affirming his military service. When the news came, yelps of delight filled the museum’s library. They never found out whether he regained his freedom. But there was hope.

Another riveting, if tragic, story was that of Philip Brimblecom. Born in 1786 in Marblehead, he grew up fishing cod, and in 1809 he sailed on his uncle’s schooner to Spain. But the ship was taken off the coast of Spain and impounded by the French government. Brimblecom went to work aboard a French merchant ship, but then it was seized, and Brimblecom was jailed in England.

He eventually escaped and found an America-bound ship. But by this point the war had begun, and Brimblecom was captured again. In September 1812, he was exchanged as a prisoner of war.

Undeterred, he signed up for the Constitution the same month. During a battle in December 1812, a cannonball took away his arm at the elbow.

“Everything bad that can happen in seafaring happened to him,” said Matthew Brenckle, the museum’s research historian.

He could not find work, and wrote the Navy seeking a job and increase in his $6 monthly pension.

Brimblecom was given a job in the Charlestown Navy Yard in 1816, but later wrote and asked them to “look after a poor distressed crippled sailor.” He died at 38.

Such stories show the dangers and unforgiving nature of life at sea, and the sacrifice of those who served during what many consider the country’s second war of independence.

Yet hundreds of crew members remain just names on a muster, and researchers say their work is far from done. As word of the project has spread, descendants of sailors have contacted the museum with potential leads, and researchers are hopeful they will continue to make progress.

“We find out more practically every single day,” Brenckle said.

Peter Schworm can be reached at schworm@globe.com. Follow him on Twitter @globepete.